Screw conveyor system for durable press apparatus

ABSTRACT

A durable press apparatus has an oblong treating chamber with doors at the ends and with an internal screw conveyor for receiving wire hangers for articles to be treated. The screw conveyor comprises a pipe having a spiral peripheral groove or thread thereon for progressively advancing the hangers as the conveyor is rotated. The conveyor is supported by open-sided bearings each comprising a top bearing segment and two unopposed bottom segments to allow different types of hangers to move easily through the bearings. At the ends of the chamber there are load and unload racks having screw conveyors thereon engageable with the adjacent ends of the internal conveyor when the racks are shifted towards the chamber respectively into load and unload positions. The entire conveyor system is driven from one of the racks to load the chamber from one end simultaneously as the chamber is unloaded from the other end.

United States Patent 1 Hendren I Nov. 6, 1973 SCREW CONVEYOR SYSTEM FORDURABLE PRESS APPARATUS [75] Inventor: Charles W. Hendren, Reading, Ohio[73] Assignee: McGraw-Edison Company, Elgin, I11.

[22] Filed: Feb. 18, 1972 [21] Appl. No.: 227,409

[52] US. Cl 214/17 R, 34/236, 198/89, 198/213 [51] Int. Cl. B65g 65/46[58] Field of Search 214/17 R, 18 R; 198/213, 89; 34/236, 105

I56| References Cited UNITED STATES PATENTS 3,644,085 2/1972 Beclcy etal. 34/37 X 902,530 10/1908 Gustavscnm. 198/213 2,620,917 12/1952Dahlbcrg 198/213 3,252,200 5/1966 Gulde et al. 214/18 R X 3,178,0124/1965 Weiss et al 198/213 FOREIGN PATENTS OR APPLICATIONS 1,531,0817/1969 Germany 198/213 1,805,034 7/1970 Germany 198/213 PrimaryExaminer-Evon C. Blunk Assistant Examiner-Bruce H. Stoner, Jr.AttorneyGeorge H. Fritzinger [57] ABSTRACT A durable press apparatus hasan oblong treating chamber with doors at the ends and with an internalscrew conveyor for receiving wire hangers for articles to be treated.The screw conveyor comprises a pipe having a spiral peripheral groove orthread thereon for progressively advancing the hangers as the conveyoris rotated. The conveyor is supported by open-sided bearings eachcomprising a top bearing segment and two unopposed bottom segments toallow different types of hangers to move easily through the bearings. Atthe ends of the chamber there are load and unload racks having screwconveyors thereon engageable with the adjacent ends of the internalconveyor when the racks are shifted towards the chamber respectivelyinto load and unload positions. The entire conveyor system is drivenfrom one of the racks to load the chamber from one end simultaneously asthe chamber is unloaded from the other end.

16 Claims, 14 Drawing Figures PMENTEDHUV s 1975 SHEET 2 OF 6 RNJ\lllilll. Illlllllllllllll I III! Jill

PAIENIEnmv s 1975 3370.148

SHEEI 8 0F 6 FIG. 10

SCREW CONVEYOR SYSTEM FOR DURABLE PRESS APPARATUS The present conveyorsystem is adapted especially for use with durable press apparatus of thecharacter disclosed in the pending Forg et al. application Ser. No.179,781, filed Sept. 13, 1971, and entitled DURABLE PRESS METHOD ANDAPPARATUS. However, no unnecessary limitation of the present conveyorsystem to such apparatus is intended since the present conveyor systemis usable in many other applications where it is desired to conveyhangered articles.

An object of the invention is to provide an improved screw conveyor forhangered garments wherein the conveyor is supported by open-sidedbearings each comprising a single top bearing segment and two unopposedbottom bearing segments to enable easier passage of hangers through thebearings.

Another object is to provide such improved conveyor wherein the bearingsegments comprise plastic bearing members supported in slotted holdersto permit greater variation in temperature and humidity conditions.

Another object is to provide a conveyor system for a durable pressapparatus which permits loading a treating chamber at one endsimultaneously as the chamber is unloaded at the other end.

Another object is to provide such conveyor system comprising loading andunloading conveyor racks at the opposite ends of the treating chambershiftable from the chamber to allow the chamber to be opened and back tothe chamber into drive coupling engagement with the internal conveyor ofthe treating chamber.

Another object is to provide such load-unload conveyor system whereinthe whole system is driven from one of the conveyor racks.

Another object is to provide such system with conveyor rackshavingindividual drive motors controlled according to the couplingengagement of the conveyor racks with the internal conveyor.

These and other objects of the invention reside in providing a conveyorsystem for garment-treating apparatus which permits easy and economicalloading and unloading of the treating chamber while maintaining thegarments in a clean condition.

In the description of the invention reference is had to the accompanyingdrawings, of which:

FIG. 1 is an end view of a treating chamber with internal screwconveyors and with loading and unloading doors at the ends;

FIG. 1A is a sketch illustrating the overall conveyor system accordingto the invention;

FIG. 2 is a side elevation showing one of the bearings for the internalscrew conveyor;

FIG. 3 is a side view of one of the hanger brackets for the bearings;

FIG. 4 is an end view of the loading end of the chamber showing thescrew conveyors of a loading rack just short of engaging the internalconveyor of the chamber;

FIGS. 5 and 6 are end views of the chamber showing respectively theloading and unloading racks in operation positions;

FIG. 7 is a perspective view of the inner end of the loading rack;

FIG. 8 is a view showing the latch for holding a rack in this innerengaged position;

FIG. 9 is a side view of the latch for each rack;

FIG. 10 is a cross-sectional view of the intercoupling pin and keybetween and the rack conveyors and internal conveyor.

FIGS. 11 and 12 are views of the drive motors and couplings for therespective conveyors on the loading and unloading racks; and

FIG. 13 is a schematic circuit diagram of the electrical drive systemfor the conveyors.

A durable press apparatus as before referred'to comprises an elongatetreating oven or chamber 10 for subjecting garments to an atmosphere offormaldehyde and sulphur dioxide gases and steam, means for next heatingthe chamber to a temperature of the order of 250F. and circulating meansfor then flushing the chamber with cool outside air before the garmentsare removed. The present invention is adapted especially for such atreating chamber having loading and unloading doors 1 1 and 12 at itsopposite ends, and having two internal screw conveyors 13 and 14 alongthe length thereof. (See FIG. 1 In the present design, each screwconveyor comprises a hollow pipe 15 having a wire helix l6 wound thereonand welded thereto (FIG. 2). Each bearing 17 for the conveyor isopen-sided so that wire hangers 18 engaging the spiral groove 16a of theconveyor may travel through the bearings as the conveyor is rotated.Each bearing 17 comprises one upper bearing segment 17a and a pair ofseparate unopposed lower segments 17b and 170 spaced beyond the ends ofthe upper segment.

The segments of each bearing 17 are carried by a C- shaped hangerbracket 19 having L-shaped mounting brackets 20 (FIG. 3) welded to theupper ends thereof which are in turn bolted to a steam pipe 21 ofrectangular cross section clamped to the ceiling of the chamber 10.Welded to the upper leg 19a of each hanger bracket is a dependinginverted U-channel 22 with stop ins 22a at the ends in which is mounteda bar-shaped bearing member 23 of plastic material, preferably, of 10percent glass-filled Teflon because of the conditions in the chamber.This bearing member 23 rides on the screw conveyor and spans a pluralityof threads of the wire helix 16. Two adjusting screws 23a threadedthrough the top wall 22b of the channel 22 enable the bearing member tobe adjusted into even engagement with the screw conveyor.

The bottom leg 19b of the hanger bracket 19 has an angle iron 24 weldedthereto which embraces a side and bottom portion of a U-shaped trough 25extending along the full length of the screw conveyor. This trough ismounted below the screw conveyor but is shifted circumferentially 30against the direction of rotation of the conveyor and displacedrectilinearlyin the direction of rotation as shown in FIG. 3. Centrallylocated in the trough and extending along the length thereof is arectangular steam pipe 26. Between this steam pipe and the side walls ofthe trough is a pair of bar-shaped bearing members 27 and 28 positionedalong the trough beyond the ends of the upper bearing member 23 so thatthe bearing 17 has no opposed members. Thus, if the hook of a hanger 18should be bent causing the hanger to be tilted as it goes through theupper bearing segment, the hanger can not strike the lower bearingsegments and get caught when it is tilted. The bearing members 27 and 28are also preferably made of 10 percent glass-filled Teflon. The upperfaces of bearing members 27 and 28 are tapered at 35 and 65 respectivelyso that they engage the screw conveyor in a tangential relationship.These bearing members likewise span a plurality of threads 16b of thescrew conveyor.

As shown in FIG. 3, the screw conveyor receives the hangers 18 from theside away from the hanger brackets 19 and is rotated in a directiontending to draw the hooks of the hangers over the conveyor rod towardsthe hanger brackets. Looking at the conveyor from the entry end of abearing 17 (left side as shown in FIG. 2) the conveyor rod is turnedclockwise and the threads 16b of the wire helix 16 are left-handed.

Steam of a low pressure is led from a source (not shown) through a tube80 to a T-coupling 81 (FIG. 4) and from this coupling through tubes 82and 83 to the upper steam pipes 21. At the far end of the pipes 21 thesteam is led via tubes 84 (FIG. 2) to the adjacent ends of the pipes 26in trough 25. After passing the length of the pipes 26 the steam is ledoff via tubes 85 and 86 (FIG. 1) through traps not shown.

At one end of the chamber 10 is a loading rack 30 (FIG. and at the otherend an unloading rack 31 (FIG. 6) of which the loading rack 30 carries apair of screw conveyors 32 and 33 and the unloading rack a pair of screwconveyors 34 and 35. These screw conveyors are the same type as theinternal conveyor above-described. Also, these external screw conveyorsare supported in the same manner as in the chamber by bearings 17ecarried by C-shaped hanger brackets 192 but the plastic bearing membersof these internal bearings the bearing members 23:: and 27e shown inFIG. 7 are preferably made of high molecular weight polyethylene. Sincethe external conveyors need not be heated to avoid dripping ofcondensation on the garments the troughs 25e of the external conveyorsmay have centrally positioned solid bars instead of the steam pipes 26and the hanger brackets 19c are bolted to overhead angle irons 37instead of to stream pipes as in the case of the internal conveyors. Theangle irons 37 for the respective racks 30 and 31 are interconnected bytransverse bars 38 forming respective carriages 39 and 40 for therespective racks. These carriages are suspended from stationary overheadrails 41 and 42 (FIGS. 5, 6 and 8) by way of bolts 43 leading from theouter ends of the transverse bars 38. These bolts are secured to rollerskate mechanisms 44 (FIG. 7) riding in the rails 41 and 42. For example,each rail 41 and 42 is of an inverted U-shape having flanged lips 45 and46 which are turned inwardly from the side walls and'separated by anintervening slot 47 lengthwise of the rail. The bolts 43 traverse theseslots, and each skate mechanism 44 comprises a frame 44a secured to thebolt and pairs of rollers 44b which ride on the flanged lips 45 and 46of the rails 44 and 42. Thus each conveyor rack 30 and 31 can be shiftedto and from the chamber 10 to permit the doors l1 and 12 to be openedand closed. Typically, each conveyor rack is about 14' long andisshiftabie through a distance of about 6 to provide a conveyor systemleading about from each end of the treating chamber.

Journaled in apertured lugs 49 depending from the angle irons 37 is across rod 50 for each conveyor rack having crank arms at the endsforming handles 51 (FIGS. 5, 6 and 8). Secured to the cross rod 50midway between the angle irons 37 of each conveyor rack is a latch arm52 having a slotted end portion engaging a plunger 53 of a latch 54bolted to a cross bar 55 also mounted on the respective carriage rack(FIG. 9). The

operator can reach up and grip the handle 51 to shift the rack along thestationary rails 41 and 42 but when the rack reaches an end position atthe treating chamher a beveled end portion 53a of the plunger 53 iscammed into registry with a latch keeper S6 bolted to a cross bar 57welded between the stationary rails 41 and 42, thus latching the rack inits inner load or unload position. When the operator grips the handle 51and moves it in a direction away from the chamber 10 the handle is atfirst turned to unlatch the conveyor rack and then the rack is moved bycontinuing outward thrust on the handle along the rails 41 and 42.

The screw conveyors 32 and 33 on the load and unload racks 30 and 31 aremounted in alignment with the respective internal conveyors l3 and 14 ofthe chamber 10 (FIG. 4) and are terminated by centering pins 58 whichengage the respective pipes l5 of the internal conveyors as the load andunload racks 30 and 31 are moved into their inner latched positions.Each centering pin 58 has an open-ended slot 59 (FIG. 10) runninglengthwise thereof which leads to a transverse slot 60 at the base ofthe pin. Secured in the lengthwise slot 59 near the tip of the pin 58 isa cantilever spring 62 and secured by bolts 63 to the rear portion ofeach cantilever spring is a key 64 that extends crosswise through thetransverse slot 60 and beyond the periphery of the centering pin. Eachkey has a beveled face at its outer end directed toward the outer end ofthe centering pin so that the key is cammed inwardly as the centeringpin engages the open pipe of the internal screw conveyor. Uponthereafter rotating the external screw conveyor the same will turnrelative to the internal conveyor until the key 64 comes intoregistration with an open-ended slot 65 in the internal conveyor (FIG.4). When this registration occurs the key is snapped outwardly by springforce to interlock the conveyors of the external racks with the internalconveyor to provide a drive coupling therebetween. The slot 65 at eachend of the internal conveyors is so oriented that when the dirveconnection occurs the wire helix 16 of the internal conveyor will be inregistry with the wire helix of the external conveyor.

At the far end of each external conveyor on the load rack 30 there is adrive motor 66 (FIG. 11) operating through a speed reducer 67, and atthe far end of each screw conveyor on the unloading rack 31 there is adrive motor 68 (FIG. 12) operating through a speed reducer 69. Thereducers 67 are connected to the conveyors of the loading rack 30through overriding clutches and the reducers 69 are connected to theconveyors of the unloading racks through spring loaded spline-typecouplings 71. The drive motors 68 on the unloading racks 31 are used todrive the entire conveyor system when the loading racks are also coupledto the internal conveyors. Thus the overriding clutches 70 serve toprotect the reducers 67 when the conveyors are driven from the unloadingrack, and the spring-loaded spline-type couplings 71 serve to maintaintension of the drive connections between the conveyors and to allow forlengthwise variations.

When the loading rack 30 is in its detached outer position it can beloaded from the far end by running the drive motors 66. However, whenthe conveyors 32 and 33 of the loading rack 30 are attached to theinternal conveyors 13 and 14 the carriage 39 abuts against arack-position limit switch 72 on the stationary frame to disable thedrive motors 66. (FIGS. 7 and 13). When the unloading rack 31 is in itsdetached position away from the treating chamber it can be unloaded atthe far end by running the drive motors 68. The motors 68 are renderedinoperable by a rack-position limit switch 73 (FIG. 13) when theunloading rack 31 is latched in coupled relationship with the internalconveyors. The limit switch 73 on the unloading rack is like the limitswitch 72 for the loading rack. If the conveyors 32 and 33 of theloading rack are coupled at the same time to the intemal conveyors 13and 14, the limit switch 72 restores the power circuit (FIG. 13) toenable the drive motor 68 of the unloading rack to drive the entireconveyor system.

In addition there is a safety limit switch 74 mounted on the back end ofthe unloading rack 31 which is operated by a hanger when the samereaches the far end of the unloading rack 31. This switch is normallyclosed and connected in the line to the unload motor 68 as shown in FIG.13 to stop the motor when the switch is operated.

Also, the control system includes two operator or manual switches 75 and76 (FIG. 13) at the loading and unloading racks 30 and 31 respectively.When the loading rack 30 and chamber are filled say 90 hangers at eachlocation and the unloading rack 31 is empty, the operator at loadingrack may close switch 75 to start unloading the chamber 10 onto theunloading rack 31 and to start simultaneoulsy the reloading of chamber10 from the loading rack 30. This operation will continue so long asswitch 75 is held closed until safety limit switch 74 on the unloadingrack 31 is operated at which time all of the hangers from the chamber 10will have been conveyed onto the unloading rack 31. When the loading andunloading racks 30 and 31 are detached from the chamber 10 therespective conveyors 32-33 and 34-35, are controlled by the respectiveoperator switches 75 and 76.

By way of typical example, the pitch of the screw conveyors of the loadand unload racks is /1, inch and of the internal conveyor 13 and 14 is linches. Further, the garments are hung in alternate groove convolutionsgiving a space between garments of l /2 inches on the load and unloadracks and of 3 inches in the treating chamber 10. The conveyors aredriven to transfer the garments from the load rack at a rate of about 17per minute and simultaneously from the treating chamber to the unloadingrack at about 34' per minute. In view of these conditions a spiral wireinch in diameter is required for each wire helix to prevent skipping anddropping of hangers. Further, the use of round wire for the helixprovides a rounded surface engaging the bearing members to reducefriction and wear.

The embodiment of my invention herein particularly shown and describedis intended to be illustrative and not necessarily limitative since thesame is subject to changes and modifications without departure from thescope of my invention, which I endeavor to express according to thefollowing claims.

I claim:

1. An apparatus for treating fabric articles to provide the same with adurable press comprising an elongate treating chamber having a loadingdoor at one end and an unloading door at the other end, a screw conveyoralong the length of said chamber and journal bearings for said screwconveyor supported from the ceiling of the chamber, said screw conveyorhaving a spiral groove to receive hanger hooks for said articles andcause the articles to be carried lengthwise of said chamber as theconveyor is rotated, each of said journal bearings comprising an upperbearing portion and two separate lower bearing portions located beyondthe ends of said upper bearing portion in unopposed relation to saidupper bearing portion, said bearing portions comprising bar-shapedmembers traversing a multiplicity of thread convolutions of saidconveyor while leaving transverse spaces therethrough via the grooveconvolutions of the conveyor enabling said hooks to travel through saidbearings, and each of said lower bearing portions being displacedagainst the direction of rotation of said conveyor from a positiondiametrically opposite said upper portion for clearing said hanger hooksreceived by said screw conveyor from the side away from said lowerbearing portion.

2. An apparatus for treating fabric articles to provide the same with adurable press comprising an elongate treating chamber having loading andunloading doors, a screw conveyor along the length of said chamber andjournal bearings for said screw conveyor supported from the ceiling ofthe chamber, said screw conveyor having a spiral groove to receivehanger hooks for said articles and cause the articles to be carriedlengthwise of said chamber as the conveyor is rotated, each of saidjournal bearings comprising an upper bearing portion and a separatelower bearing portion of plastic material traversing a multiplicity ofthread convolutions of said conveyor while leaving transverse spacestherethrough via the groove convolutions of the conveyor enabling saidhooks to travel through said bearings, and each of said lower portionscomprising two spaced parallel bearing members having end facestangentially engaging said conveyor at points spaced circumferentiallyabout said conveyor and comprising a steam pipe clamped between saidbearing members.

3. The apparatus set forth in claim 2 wherein said upper bearing portionis symmetrically located relative to a vertical plane through the axisof said conveyor, said lower bearing portion is shifted against thedirection of rotation of said conveyor by a predetermined angle fromsaid vertical plane, and said parallel bearing members of said lowerbearing portion are displaced rectilinearly in the direction of rotationof said conveyor from a plane parallel therewith through said axis.

4. An apparatus for treating fabric articles to provide the same with adurable press, comprising an elongate treating chamber having loadingand unloading doors, an internal screw conveyor in said treating chambersupported rotatably from the ceiling of the chamber, an external rack ata door of said chamber, guide rails for said rack permitting the rack tobe shifted to and from said chamber to permit said door to be open andclosed, said rack having a screw conveyor thereon positioned foralignment with said internal screw conveyor, coupling means engaged byshifting said rack towards said chamber to form a drive connectionbetween said internal and external conveyors, and a latch for lockingsaid rack in its inner engaged position.

5. The apparatus set forth in claim 4 including a drive motor on saidrack for driving both said external and loading end, guide rails at theends of said chamber for said respective racks permitting the racks tobe shifted towards and away from said chamber, a screw conveyorrotatably supported on each of said racks for coupling engagement withthe internal conveyor in said chamber as the racks are shifted intotheir inner positions, a drive motor on each of said racks for therespective conveyor, and limit switches controlled by movement of theracks into and out of coupled relationship with said internal conveyorfor abling and disabling said respective motors.

7. The apparatus set forth in claim 6 wherein the drive motor on saidloading rack is rendered inoperable when said loading conveyor iscoupled to said internal conveyor.

8. The apparatus set forth in claim 6 wherein the drive motor on saidunloading rack is rendered inoperable when only said unloading conveyoris coupled to said internal conveyor.

9. The apparatus set forth in claim 8 including means controlled by saidlimit switches for enabling the drive motor on said unloading conveyorto drive the entire conveyor system when said loading conveyor is alsocoupled to said internal conveyor.

10. An apparatus for treating fabric articles to provide the same with adurable press, comprising an elongate treating chamber provided withdoors at its opposite ends and with a screw conveyor along the lengththereof, loading and unloading racks at the opposite ends of saidchamber each having a screw conveyor rotatably mounted thereon, meansmounting said racks for shifting movement towards and away from saidchamber to bring the screw conveyors thereof into and out of couplingengagement with the internal screw conveyor in said chamber, and a drivemotor for said unloading rack for driving all of said conveyors inunison whereby to unload said chamber onto said unloading racksimultaneously as said chamber is loaded from said loading rack.

11. The apparatus set forth in claim 10 including a drive motor also forthe loading rack, and a one-way over-riding clutch between said drivemotor and respective conveyor of said loading rack enabling the drive ofsaid loading rack by the drive motor of said unloading rack via saidinternal conveyor.

12. The apparatus set forth in claim 11 including a spring loadedspline-type coupling between the drive motor and conveyor of saidunloading rack to maintain tension on the drive coupling between saidinternal conveyor and said rack conveyors.

13. In a screw conveyor system for a durable press apparatus: thecombination of a treating chamber having loading and unloading doors atthe opposite ends, an internal screw conveyor rotatably supported fromthe top of said treating chamber and extending substantially from one ofsaid doors to the other, said screw conveyor comprising a pipe having ahelical wire secured thereon for receiving hanger hooks between wireconvolutions and advancing the hangers as the conveyor is rotated,loading and unloading racks at the opposite ends of said chamber eachhaving a screw con veyor rotatably supported thereon and positioned toenter into drive engagement with the said internal conveyor as the racksare shifted into inner positions at the ends of said chamber, a couplingmeans between said internal conveyor and said external conveyors of saidracks adapted to form a drive engagement only when the helical wires ofsaid conveyors have come into an even spiral registration with eachother, and a drive motor on one of said racks for rotating the entireconveyor system whereby to shift said hanger hooks from said loadingrack into said chamber simultaneously as the hanger hooks in saidchamber are shifted onto said unloading rack.

14. The screw conveyor system set forth in claim 13 including acentering pin on the conveyor of each of said racks engageableinternally with the conveyor in said chamber as the rack is moved intoan inner latched position, a spring-loaded key in said centering pinbiased radially outwardly therefrom, and a slot in the end portion ofsaid internal conveyor for receiving said key to provide a driveconnection between said conveyors when the helical wires on theconveyors are in registry with each other, wherein said slot in the endportion of said internal conveyor is open-ended topermit readydetachment of said racks from said internal conveyor when the racks areunlatched.

15. In an apparatus for treating fabric articles to provide the samewith a durable press: the combination of an elongate treating chamberhaving loading and unloading doors respectively at the opposite endsthereof, an internal rotatably mounted screw conveyor in said treatingchamber along the length thereof adapted for receiving the hooks ofhangers for said fabric articles and for conveying the hangers alongsaid chamber in the direction from said loading door to said unloadingdoor as said conveyor is rotated, respective loading and unloading racksat the load and unload ends of said chamber each shiftable to and fromsaid chamber, screw conveyors on said laoding and unloading racks movedinto coupled relation with said internal conveyor as said racks areshifted toward said chamber respectively into load and unload positions,a drive motor on said unloading rack coupled to the respective screwconveyor thereof, a manual operators switch on said loading rack, andcircuit means rendered operative only when both of said rack conveyorsare coupled to said internal conveyor for enabling said drive motor ofthe unloading rack to be started by said manual switch of the loadingrack.

16. The apparatus set forth in claim 15, including a safety limit switchconnected in said circuit means and mounted on said unloading rack atthe far end of said respective conveyor for operation by a hanger onsaid respective conveyor to stop said drive motor when said hangerreaches the end of the conveyor.

1. An apparatus for treating fabric articles to provide the same with adurable press comprising an elongate treating chamber having a loadingdoor at one end and an unloading door at the other end, a screw conveyoralong the length of said chamber and journal bearings for said screwconveyor supported from the ceiling of the chamber, said screw conveyorhaving a spiral groove to receive hanger hooks for said articles andcause the articles to be carried lengthwise of said chamber as theconveyor is rotated, each of said journal bearings comprising an upperbearing portion and two separate lower bearing portions located beyondthe ends of said upper bearing portion in unopposed relation to saidupper bearing portion, said bearing portions comprising bar-shapedmembers traversing a multiplicity of thread convolutions of saidconveyor while leaving transverse spaces therethrough via the grooveconvolutions of the conveyor enabling said hooks to travel through saidbearings, and each of said lower bearing portions being displacedagainst the direction of rotation of said conveyor from a positiondiametrically opposite said upper portion for clearing said hanger hooksreceived by said screw conveyor from the side away from said lowerbearing portion.
 2. An apparatus for treating fabric articles to providethe same with a durable press comprising an elongate treating chamberhaving loading and unloading doors, a screw conveyor along the length ofsaid chamber and journal bearings for said screw conveyor supported fromthe ceIling of the chamber, said screw conveyor having a spiral grooveto receive hanger hooks for said articles and cause the articles to becarried lengthwise of said chamber as the conveyor is rotated, each ofsaid journal bearings comprising an upper bearing portion and a separatelower bearing portion of plastic material traversing a multiplicity ofthread convolutions of said conveyor while leaving transverse spacestherethrough via the groove convolutions of the conveyor enabling saidhooks to travel through said bearings, and each of said lower portionscomprising two spaced parallel bearing members having end facestangentially engaging said conveyor at points spaced circumferentiallyabout said conveyor and comprising a steam pipe clamped between saidbearing members.
 3. The apparatus set forth in claim 2 wherein saidupper bearing portion is symmetrically located relative to a verticalplane through the axis of said conveyor, said lower bearing portion isshifted against the direction of rotation of said conveyor by apredetermined angle from said vertical plane, and said parallel bearingmembers of said lower bearing portion are displaced rectilinearly in thedirection of rotation of said conveyor from a plane parallel therewiththrough said axis.
 4. An apparatus for treating fabric articles toprovide the same with a durable press, comprising an elongate treatingchamber having loading and unloading doors, an internal screw conveyorin said treating chamber supported rotatably from the ceiling of thechamber, an external rack at a door of said chamber, guide rails forsaid rack permitting the rack to be shifted to and from said chamber topermit said door to be open and closed, said rack having a screwconveyor thereon positioned for alignment with said internal screwconveyor, coupling means engaged by shifting said rack towards saidchamber to form a drive connection between said internal and externalconveyors, and a latch for locking said rack in its inner engagedposition.
 5. The apparatus set forth in claim 4 including a drive motoron said rack for driving both said external and internal conveyors. 6.The apparatus set forth in claim 4 wherein said chamber has a loadingdoor at one end and an unloading door at the opposite end, including aloading rack at said loading end and an unloading rack at said unloadingend, guide rails at the ends of said chamber for said respective rackspermitting the racks to be shifted towards and away from said chamber, ascrew conveyor rotatably supported on each of said racks for couplingengagement with the internal conveyor in said chamber as the racks areshifted into their inner positions, a drive motor on each of said racksfor the respective conveyor, and limit switches controlled by movementof the racks into and out of coupled relationship with said internalconveyor for abling and disabling said respective motors.
 7. Theapparatus set forth in claim 6 wherein the drive motor on said loadingrack is rendered inoperable when said loading conveyor is coupled tosaid internal conveyor.
 8. The apparatus set forth in claim 6 whereinthe drive motor on said unloading rack is rendered inoperable when onlysaid unloading conveyor is coupled to said internal conveyor.
 9. Theapparatus set forth in claim 8 including means controlled by said limitswitches for enabling the drive motor on said unloading conveyor todrive the entire conveyor system when said loading conveyor is alsocoupled to said internal conveyor.
 10. An apparatus for treating fabricarticles to provide the same with a durable press, comprising anelongate treating chamber provided with doors at its opposite ends andwith a screw conveyor along the length thereof, loading and unloadingracks at the opposite ends of said chamber each having a screw conveyorrotatably mounted thereon, means mounting said racks for shiftingmovement towards and away from said chamber to bring the screw conveyorsthereof into and out of coupling engagement with the internal screwconveyor in said chamber, and a drive motor for said unloading rack fordriving all of said conveyors in unison whereby to unload said chamberonto said unloading rack simultaneously as said chamber is loaded fromsaid loading rack.
 11. The apparatus set forth in claim 10 including adrive motor also for the loading rack, and a one-way over-riding clutchbetween said drive motor and respective conveyor of said loading rackenabling the drive of said loading rack by the drive motor of saidunloading rack via said internal conveyor.
 12. The apparatus set forthin claim 11 including a spring loaded spline-type coupling between thedrive motor and conveyor of said unloading rack to maintain tension onthe drive coupling between said internal conveyor and said rackconveyors.
 13. In a screw conveyor system for a durable press apparatus:the combination of a treating chamber having loading and unloading doorsat the opposite ends, an internal screw conveyor rotatably supportedfrom the top of said treating chamber and extending substantially fromone of said doors to the other, said screw conveyor comprising a pipehaving a helical wire secured thereon for receiving hanger hooks betweenwire convolutions and advancing the hangers as the conveyor is rotated,loading and unloading racks at the opposite ends of said chamber eachhaving a screw conveyor rotatably supported thereon and positioned toenter into drive engagement with the said internal conveyor as the racksare shifted into inner positions at the ends of said chamber, a couplingmeans between said internal conveyor and said external conveyors of saidracks adapted to form a drive engagement only when the helical wires ofsaid conveyors have come into an even spiral registration with eachother, and a drive motor on one of said racks for rotating the entireconveyor system whereby to shift said hanger hooks from said loadingrack into said chamber simultaneously as the hanger hooks in saidchamber are shifted onto said unloading rack.
 14. The screw conveyorsystem set forth in claim 13 including a centering pin on the conveyorof each of said racks engageable internally with the conveyor in saidchamber as the rack is moved into an inner latched position, aspring-loaded key in said centering pin biased radially outwardlytherefrom, and a slot in the end portion of said internal conveyor forreceiving said key to provide a drive connection between said conveyorswhen the helical wires on the conveyors are in registry with each other,wherein said slot in the end portion of said internal conveyor isopen-ended to permit ready detachment of said racks from said internalconveyor when the racks are unlatched.
 15. In an apparatus for treatingfabric articles to provide the same with a durable press: thecombination of an elongate treating chamber having loading and unloadingdoors respectively at the opposite ends thereof, an internal rotatablymounted screw conveyor in said treating chamber along the length thereofadapted for receiving the hooks of hangers for said fabric articles andfor conveying the hangers along said chamber in the direction from saidloading door to said unloading door as said conveyor is rotated,respective loading and unloading racks at the load and unload ends ofsaid chamber each shiftable to and from said chamber, screw conveyors onsaid laoding and unloading racks moved into coupled relation with saidinternal conveyor as said racks are shifted toward said chamberrespectively into load and unload positions, a drive motor on saidunloading rack coupled to the respective screw conveyor thereof, amanual operator''s switch on said loading rack, and circuit meansrendered operative only when both of said rack conveyors are coupled tosaid internal conveyor for enabling said drive motor of the unloadingrack to be started by said manual switch of the loading rack.
 16. Theapparatus set forth in claim 15, including a safety limit switchconnected in said circuit mEans and mounted on said unloading rack atthe far end of said respective conveyor for operation by a hanger onsaid respective conveyor to stop said drive motor when said hangerreaches the end of the conveyor.